Published In
Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit
Document Type
Post-Print
Publication Date
2005
Subjects
Railroad cars, Topology
Abstract
Stress constraint is a hard issue for structural topology optimization, especially for large-scale structures, e.g. railcars. Another technique is proposed to combine a sizing optimizer with metamodelling for topology optimization. At the lower level, for each topology design sampled within the topology design space, a sizing optimizer finds feasible and optimal solutions in terms of sizing variables (plate thickness in continuum structures). All performance constraints such as stress, displacement, and stability, are handled only at this level. At the upper level, a metamodel is built to fit all the optimal solutions found at the lower level and is optimized for topology design. The only constraints left at the upper level are topological constraints and topological variable bounds. Only the objective function (e.g. weight) versus topological variables, and not the constraints, is approximated. The number of topology design variables is much smaller than those used in many other topology optimization approaches. Thus it may be able to handle large-scale structural systems. It was applied to two boxcar design projects, resulting in 18 percent and 36 percent weight savings and significant reductions in manufacturing cost and total cost.
Rights
This is the post-print version. The final published version, Copyright © 2005 by Institution of Mechanical Engineers, is available here: https://doi.org/10.1243/095440905X8763
DOI
10.1243/095440905X8763
Persistent Identifier
https://archives.pdx.edu/ds/psu/42839
Citation Details
Liu, L., & Wakeland, W. (2005). Combining optimizer and metamodelling for railcar structural optimization. [Post-print] Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit, 219(1), 1-9.